how can we know if someone is truly who they say they are?
What about groups which impersonate other groups?
Even if they have the same name, how can we show uniqueness?
Perhaps we expose UIDs so that official accounts elsewhere can say “our account does NOT end in ‘…xh52’ it ends with ‘…jpr1’“
Or we keep usernames and on other platforms they must say what their username is
Perhaps Username should show change history?